         definition (read-definition dataset)
         concepts (read-concepts definition)]
     (with-db (get-db dataset)
+      (coll/drop slice)      
       (load-slice slice concepts definition)
       (index-slice slice definition))))

        group-id (apply merge
                        (map #(hash-map % (str "$" (name %))) dimensions))
        aggs (map (fn [[agg-metric [agg metric]]]
                    {agg-metric {(str "$" (name agg))
                                 (str "$" (name metric))}}) aggregations)
        group (apply merge {:_id group-id} aggs)
        project-dims (map (fn [dimension]
                            {dimension

    (when (and drakefile (.isFile drakefile))
      (run-drakefile drakefile))))

(defn ez-load-definition
  "Load the definition of a dataset.
  Does not run Drake to process data first."
  [dataset]
  (let [dataset (name dataset)
        definition (read-definition dataset)]
    (save-dataset-definition dataset definition)))

(defn ez-load-concepts
  "Load just the concepts for a dataset.
  Does not run Drake to process data first."
